Shoe sewing machine



March 11, 1952 SHOE O. R. HAAS SEWING MACHINE Filed May 24, 1949 50 v f E 52 l \Q i Inventor Otto R Haas Z5 '59 is Attorney Patented Mar. 11, 1952 SHOE SEWING MACHINE Otto R. Haas, Wenham, Mass., assignor to United Shoe Mach nery Corporation, Flemington, N. J a corporation of New Jersey Application May 24, 1949, SerialNo. 95,043

7 Claims. (01. 112-41) The present invention relates to improvements in wax thread shoe sewing machines and more particularly to an arrangement of a mounting bracket and heating devices for a tension wheel together with a cover which is movable for rendering the heating devices accessible, by the use of which greater efficiency in heating is obtainable and other beneficial advantages are gained, the achieving of which constitute the objects of the invention.

The invention is herein illustrated as embodied in a machine similar to that disclosed in United States Letters Patent No. 1,971,575, granted August 28, 1934, and No. 2,219,933, granted October 29, 1940, both upon applications of A. R. Morrill. The machine of the patents is provided with a hollow main frame having forwardly projecting vertical walls between which certain of the stitch forming devices are mounted, including a curved hook needle and a looper for laying the thread in the hook of the needle. At the top of the machine of the patents is a bearing bracket in which is mounted a take-up and a thread tension. In the bracket is also mounted a heater for maintaining the wax on the thread in softened condition as it passes from the tension to the take-up. To maintain the air surrounding the tension and take-up in heated condition a cover also is provided in the patented machines, enclosing these devices. The tension of the patented machines is heated in part by conduction and in part by convection through the air surrounding it. Because the heater is located at some distance from the tension it requires considerable time in preparing the machine for operation for transferring heat through the air and bearing bracket to soften the wax on the thread engaging the tension and take-up.

According to an important feature of the present invention the tension for a wax thread shoe sewing machine of the type referred to is mounted on a bracket secured to the machine frame and is provided with a cover hinged to the bracket having, in the cover in close spaced relation to the tension, a heater arranged to be movable with the cover to a position remote from the tension when the cover is opened so that there will be no danger of injury from highly heated surfaces to the hands of the operator while manipulating the thread on the tension. As illustrated, heat transference is accomplished by radiation which is more rapid than conduction or convection, less time being required to prepare the machine for operation and a closer control of the heat bein obtained. This featured the invention is illus- I 3 trated as being applied tension is in the form of a wheel rotatably mounted in the bracket andthe heater consists of a;

, axial alinement with the tension, wheel.

to a machine in which the of this feature, along the axis of the hinge for;

the cover to cause the connections to-be rotated rather than bent transversely when the cover. is

opened, thus reducing the tendency to breakage in the connections or injury to the insulation.

thereon.

These and other features of the invention con? sist in the devices, combinations and arrange; ments of parts hereinafter described and claimed which, together with the advantages to be ob. tained therefrom, will readily be understood from the following description taken in connection with the accompanying drawings, in which Fig. 1 is a view in right side elevation showeing a portion of the sewing head in a curved hook needle chainstitch sewing machine, only so much of the machine being shown as is necessary to illust'ate the present invention;

Fig. 2 is a sectional plan view of a portion of the machine taken along the line IIII of Fig. 1;

Fig. 3 is a partial front view of the machine; and Fig. 4 is a sectional view taken along the line IV-IV of Fig. 1. a

The shoe machine illustrated in the drawings is provided with the usual stitch forming devices and actuating mechanisms for a welt shoe sewing machine comprising a curved hook needle ID, a

curved awl II, a needle looper I2, a thread arm 14, a take-up [6, a channel guide I8, and a tension wheel 20. The construction and arrangement of these devices and their actuating mechanisms are the same as in the patents above referred to.

The tension wheel 20 is of well-known construction with a series of thread guiding talbs bent alternately in opposite directions to form a groove for the reception of the thread, indicated at 22-.

When the thread is treated with hot wax before being led to the stitch forming devices it must be maintained in heated condition substantially to the point of operation of the needle, otherwise the wax on the threadwill become congealed, blocking further progress of the thread to the operating point. Before a cold machine is started in operation it is necessary to insure thorough heating of all the stitch forming devices to soften the wax thereon and to release the thread, particularly as it passes about the tension wheel 20.

To insure quick heating of the tension wheel in the machine of the present invention without blocking easy access to the wheel or subjecting the hands of the operator to danger of injury through contact with highly heated surfaces, the tension wheel 20 has disposed in substantially axial alinement therewith a hot disk 24 secured to a tension wheel and take-up enclosing cover 26 and arranged in close spaced relation to the tension wheel to heat the wheel by radiation when the cover is closed. When the cover is opened the disk is carried away from the tension wheel with the cover to a more remote position, enabling the operator to thread the tension wheel or otherwise manipulate the thread thereon without danger of injury to his hands. Also, when the cover is raised the tension wheel is allowed to cool. The cover 26 is hinged to swing substantially in theplane of the tension wheel atits upper end by a pin 28 to an upstanding lugon the upper end of a tension wheel and take up supporting bracket 30 in which the tension wheel is rotatably mounted. To provide access for adjustment or cleaning to the underlying parts, the bracket 30 has also a pivot 32 at its upper end'in the frame of the machine, indicated at 34. At the lower forward end of the bracket it is clamped by screws 36 passing througha horizontal portion of the bracket into threaded engagement with a block 38. The block 38 has a downwardly projecting arm which cornprises a-spacer clamped between forwardly projecting side wall portions of the frame 34. The lower surface of the spacer block 38 is engaged by a carrier 40 for the looper which is yieldingly pressed into engagement with the block by a re silient member 42, as more fully described in an application for United States Letters Patent Serial No. 66,753, filed September 22, 1948, in the name of John A. Miller.

In the machine of the patents referred to the lower end of the tension wheel bracket itself forms the spacing block so that if it is necessary to raise the bracket about its pivot this can be done only by removing screws similar to those indicated in the present drawings at M. These screws, however, are essential for retaining the vertical side walls of the frame in rigid condition so that without the screws there is danger of injury to the machine if the machine is operated. In the present construction, however, the bracket may be raised when the screws 35 are removed, leaving the block 38 in clamped position. The hot disk 24 is secured to the inside surface of the cover 26, a pair of screws 46 passing through the cover, through spacers 48 and into threaded engagement with the disk. To heat the disk it is formed with a diametrically disposed hollow enlargement within which is mounted an electrical resistance heater cartridge 56 retained within the disk by a pin 52 at one end passing across the enlargement and a clamp screw 54 threaded into the enlargement with its head bearing on the other end of the cartridge.

For energizin'g the cartridge electrical connections '56 are" provided extending from the cartridge along the axis of the hinge pin 28 through a channel 58 formed in the cover and through. an I elbow wiring fixture 60. The wiring fixture 6U is'rotatably mounted within an opening in an upstandingslotted lug 62 connected with the bracket 30, so arranged that the fixture is disposed in line with the pivot 28, the channel 58 providing a clear passage for the connections 56 into the fixture. To protect the electrical connections in the channel 58 a removable plate 64 bridges the channel and is secured in place by screws 66. The channel 58 is located in substantially parallel relation to the cover hinge pin 28 at the forward side of the hinge-pin within the cover so that the connections 56 extend toward the wiring fixture 60 at a small inclination. Thus, the cover may be raised without bending the electrical connections transversely to any appreciable degree, the connections being rotated with the cover to produce a slight torsional effect upon them which is less likely to produce injury in the connections than transverse bending action. To support the cover in raised position a stud B5 is mounted in the machine frame 34 at a location to be engaged by the cover.

It is apparent that by the construction described the tension wheel and take-up within the cover, starting cold, will be heated to an operating temperature more quickly than the corresponding parts in the prior construction. The tension wheel 26 will-be subject to heat radiation immediately upon closing the circuit to the heating cartridge 56 without depending upon slow heat conduction along the bracket for the tension wheel or air convection as in the patented construction. Furthermore, the temperature of the air surrounding the heating disk 24 also will be raised to a suitable operating point'and the heated air will shortly thereafter begin to fill the entire inside of the cover 26, in turn heating the take-up and thread 22.

To assist in maintaining the temperature of the parts within the cover 26 rising air currents are produced by convection from a heater 68 located in the block 38 below the forward end of the take-up l6. This heater consists of a cartridge having suitable electrical connections and intended primarily for heating the looper l2 through conduction between the undersurface of the block 38 and the carrier 46 for the looper. The forward end of the cover 26 is, for this purpose, provided with a hollow overlapping portion surrounding the take-up to receive the rising air currents and to retain them in surrounding relation to the take-up.

The nature and scope of the present invention having thus been indicated and a particular embodiment having been specifically described, what is claimed is:

1. A wax thread shoe sewing machine having a main frame, a hook needle and a needle looper in the frame, a thread tension device, a bracket secured to the frame in which the tension is mounted, and a cover for the tension device hinged to the bracket, in combination with a heater located on and within the cover arranged in close spaced relation to the tension device when the cover is closed and movable with the cover to a position more remote from the tension when the cover is opened to enable manipulation of the thread on the tension device without danger of injury to the hands of the operator.

2. A wax thread shoe sewing machine having a main frame, a hook needle and a needle looper in the frame, a thread tension wheel, a bracket secured to the frame in which the tension wheel is rotatably mounted, and a cover for the tension wheel hinged to swing substantially in the plane of the tension wheel, in combination with a disk located on and within the cover disposed in substantially axial alinementwith the tension wheel when the cover is closed and movable with the cover to a. position remote from the tension wheel when the cover swings away from the wheel, and a heater cartridge in the disk for causing the disk to heat the tension wheel by radiation when the cover is closed and to permit the tension wheel to cool when the cover is opened.

3. A wax thread shoe sewing machine having a main frame, a hook needle and a needle looper in the frame, a thread tension wheel, a bracket secured to the frame in which the tension wheel is rotatably mounted, and a cover for the tension wheel hinged to swing substantially in the plane of the tension wheel, in combination with a disk on the cover disposed in substantially axial alinement with the tension wheel when the cover is closed and movable with'the cover to a position remote from the tension wheel when the cover swings away from the wheel, a heater cartridge in the disk for causing the disk to heat the tension wheel by radiation when the cover is closed, and electrical connections extending from the heater cartridge along the axis of the hinge for the cover to cause the heater connections to be rotated rather than being bent transversely when the cover is opened.

4. A wax thread shoe sewing machine having a main frame, a hook needle and a needle looper in the frame, a thread tension wheel, a bracket secured to the frame in which the tension wheel is rotatably mounted, and a cover for the tension wheel hinged to swing substantially in the plane of the tension wheel, in combination with a disk on the cover disposed in substantially axial alinement with the tension wheel when the cover is closed and movable with the cover to a position remote from the tension wheel when the cover swings away from the wheel, a heater cartridge in the disk for causing the disk to heat the tension wheel by radiation when the cover is closed, electrical connections extending from the heater cartridge along the axis of the hinge for the cover to cause the heater connections to be rotated rather than being bent transversely when the cover is opened, and a wiring fixture through which the electrical connections extend mounted in the bracket in line with the hinge for the cover.

5. A wax thread shoe sewing machine having a main frame, a hook needle and a needle looper in the frame, a thread tension wheel, a bracket secured to the frame in which the tension wheel is rotatably mounted, and a cover for the tension wheel hinged to swing substantially in the plane of the tension wheel, in combination with a disk on the cover disposed in substantially axial alinement with the tension wheel when the cover is closed and movable with the cover to a position remote from the tension wheel when the cover swings away from the wheel, a heater cartridge in the disk for causing the disk to heat the tension wheel by radiation when the cover is closed, electrical connections extending from the heater cartridge along the axis of the hinge for the cover to cause the heater connections to be rotated rather than being bent transversely when the cover is opened, a channel being provided in the cover located in substantially parallel relation to the cover hinge for locating the electrical connections in the cover, and a removable plate enclosing the channel on the cover.

6. A wax thread shoe sewing machine having a main frame, a hook needle and a needle looper in the frame, a thread tension, a tension mounting bracket pivoted at one end of the frame, and a cover for the tension hinged to that end of the bracket at which the bracket is pivoted, in combination with a block secured to the frame, means for clamping the end of the bracket opposite the pivot to the block, and a heater in the block.

7. A wax thread shoe sewing machine having a main frame, a hook needle and a needle looper in the frame, a thread tension, a tension mounting bracket pivoted at one end to the frame, and a cover for the tension hinged to that end of the bracket at which the bracket is pivoted, in combination with a block secured to the frame, means for clamping the end of the bracket opposite the pivot to the block, a heater in the block, said cover having a hollow portion overlapping the block, and a take-up acting within the hollow overlapping portion of the cover.

OTTO R. HAAS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,658,190 Eppler Feb. '7, 1928 1,971,575 Morrill Aug. 28, 1934 2,041,945 Morrill May 26, 1936 

